The present invention relates to a performance input apparatus provided with an operating section displaceable about one or more axes, and more particularly to a technique of imparting the displaceable operating section with a virtual reactive force responsive to input operation (input operating force), by a human operator, of the operating section. For example, the performance input apparatus of the present invention is suitable for use as input apparatus of electronic musical instruments, as well as input apparatus for various games, computer-aided designing (CAD), etc.
In Japanese Patent Application Laid-open Publication No. HEI-10-177387 (hereinafter referred to as “prior art 1”), there is disclosed an apparatus which includes an operator operable by depression of a human operator, a cylindrical actuator for moving the operator and a sensor for detecting a position etc. of the operator. Driving of the actuator is controlled, on the basis of the position etc. of the operator detected by the sensor, to impart the operator with a reactive force responsive to an input operating force, by the human operator, of the operator.
In Japanese Patent Application Laid-open Publication No. HEI-10-78778 (hereinafter referred to as “prior art 2”), there is disclosed a string-instrument type performance input apparatus operable with a bow-shaped operator, which includes a photo sensor for detecting an operating speed (or velocity) and angle of the operator. The performance input apparatus also includes a pressure sensor for detecting an operating pressure applied by the operator to a slider section so that a current performance style of the bow-shaped operator (i.e., how the bow-shaped operator has been operated by a human operator) can be detected on the basis of the detected operating pressure.
The performance input apparatus disclosed in prior art 2 permits performance input, by the human operator, imitating or simulating performance styles that are commonly employed in violin-type instruments operable with a bow-shaped operator. However, with this input apparatus, which is not provided with any mechanism for imparting the operator with a reactive force responsive to an operating force applied to the operator, it is not possible to virtually reproduce, for example, a feeling of actual string rubbing with a bow-shaped operator, so that the sensory performance operation feelings obtained by the performance input apparatus tends to be very poor. This is because structural inconveniences and limitations, imposed by the provision of the photo sensor as operation detection means, make it difficult to provide a reactive force imparting mechanism capable of achieving desired reactive force characteristics responsive to input operation of the operator. If an arrangement employing a cylindrical actuator as disclosed in prior art 1 is used as the reactive force imparting mechanism, then the operator movable by the actuator would be limited to a relatively small range, and thus such an arrangement is not suited for impartment of a reactive force corresponding to relatively great displacement, such as that caused by string-rubbing operation, of the bow-shaped operator. Besides, the arrangement employing the cylindrical actuator would significantly increase the overall size of the apparatus. For these reasons, it has been considered undesirable to apply such a reactive force imparting mechanism to the conventional string-instrument type performance input apparatus.